The present invention is particularly applicable for use in a container of welding wire having a natural "cast" which means that in the free state the wire tends to seek a generally straight line condition and the invention will be described with particular reference to a natural cast type of welding wire stored as a large spool containing convolutions formed into layers of the welding wire which is payed out from the inside diameter of the spool through the upper portion of the container storing the spool. However, the invention has broader applications and may be used with any type of low twist welding wire contained in a spool to be fed from the center of the spool through the top of the container with or without a tendency to retain a generally straight condition. When welding automatically or semi-automatically it is essential that large amounts of welding wire be continuously directed to the welding operation in a non-twisted, non-distorted non-canted condition so that the welding operation is performed uniformly over long periods of time without manual intervention and/or inspection. It is a tremendously difficult task to be assured that the wire is fed to the welding operation in a non-twisted or low twist condition so that the natural tendency of the wire to seek a preordained natural condition will not be detrimental to smooth and uniform welding. To accomplish this task, welding wire is produced to have a natural cast, or low twist condition, which means, if a portion of the wire were cut into a long length and laid onto a floor the natural shape would be a straight line of the welding wire. When such wire is wrapped into a spool and a large container containing several hundred pounds of wire for automatic or semi-automatic welding, the natural tendency of the wire to remain in a straight or non-twisted condition makes the wire somewhat live when it is wrapped into an unnatural series of convolutions distorting the wire from its natural state. Thus, manufacturers produce large containers of low twist welding wire which must be removed from the container without twisting, tangling and/or introducing unwanted canting into the wire itself. For that reason, there is a tremendous amount of effort being directed merely to the concept of paying out low twist welding wire to an automatic and/or semi-automatic welding operation. If the pay out mechanism is not consistent and flaw proof, massive welding operations, which can consume a large amount of welding wire and a substantial amount of time, will be defective and require expensive reprocessing. This is a problem which must be solved by manufacturers of welding wire as they sell the welding wire in large spools to be payed out for automatic and semi-automatic welding. This problem is compounded with the trend toward even larger packages with larger stock of welding wire to thereby reduce the time required for replacement of the supply container at the automatic or semiautomatic welding operation. Consequently, there is an increased demand for a pail like container which is easily adapted to a large capacity and is constructed in a manner that withdrawing of the welding wire from the container is accomplished smoothly without disturbing the natural flow of the welding wire or twisting the welding wire with adjacent convolutions. Actual twisting and tangling of the wire can cause interruption of wire flow and drastically interrupt the welding operation. Thus, a large volume, high capacity storage or supply container for welding wire spools must be so constructed that it assures against any catastrophic failure in the feeding of a wire to the welding operation and the container. Further the payout or withdrawing arrangement of the container must be assured that it does not introduce even minor distortions in the free straight flow of the welding wire to the welding operation. Consequently, there is a substantial demand for a container and withdraw arrangement for large spools of welding wire which not only prevent tangling and disruption of the supply of welding wire to the welding operation but also prevent even minor distortions in the wire which could affect the quality of the continuous welding operation.
The welding wire stored in the supply container is in the form of a spool having multiple layers of wire convolutions laid from bottom to top, with an inner diameter of the spool being substantially smaller than the diameter of the container. Due to the inherent rigidity of the welding wire itself, the convolutions forming the layers are continuously under the influence of a force which tends to widen the diameter of the convolutions. However, as the welding wire is withdrawn from the container, the loosened wire portion tends to spring back and disturb or become entangled with other looped layers or with itself causing variations in the resistance of the wire withdrawal force. In such cases it becomes difficult to withdrawn the wire or feed the wire smoothly. In some of the prior containers, the wire spool or wire package is provided with a preselected twist when spooling the wire into the package in order to prevent torsional deformation of the wire which is being withdrawn axially from the non-rotating container. Consequently, the packaged wire of the spool tends to spring up with a greater force. Consequently, retainer rings, or members are placed on the top of the wire spool to hold the wires in the upper layers in place as they are withdrawn, convolution at a time, from the center opening of the wire spool through the top opening of the supply container. In the past, substantial effort has been devoted to the prevention of a "lost" convolution in the spool itself. This feeding error is normally prevented by a center tube of cardboard placed in the spool cavity so that all convolutions must be withdrawn from around the center tube. In the prior art, the ring itself contacts the inner surface of the container to prevent convolutions from springing above and around the outside of the retainer ring. In the past, the retainer ring generally rests upon the top of the wire spool by gravity. The ring has extended resilient members or fingers for contacting the inner surface of the container drum to protect the outside convolutions of the welding wire. Some of the prior rings have had a series of flat spring steel fingers attached to the retainer ring. These fingers tightly ride against the drum to control the outside convolutions of wire. In some instances, a cardboard ring is cut to the desired shape with a slight interference with the drum wall. This ring is held on the top of the spool by a weight which travels down the drum as the wire level is reduced. All of these arrangements present difficulties. Wire can be tangled on the outside of the ring and substantial drag can be imparted to the wire as it is being payed out or withdrawn from the container. These devices have friction contact with the container wall and substantial friction induced drag is exerted against the wire as it is being withdrawn. This is especially apparent as the withdrawing process continues toward the lower layers of wire in the container.